This invention relates to papermaking fabrics particularly drying and imprinting fabrics for use with through air drying machines. The fabric of the invention possesses a support surface which, due to its woven structure, and sanding, provides a large support surface area for the paper forming fibers to adhere to during processing while at the same time providing sufficient areas in which the fibers remain uncompressed producing a paper product with high bulk, superior absorptive qualities, a soft texture and improved strength.
Numerous attempts have been made to provide a papermaking fabric capable of producing a paper product with increased bulk which provides for a softer and more absorbent product. Combined with increased bulk, the product must include improved flexibility while maintaining acceptable or improved strength. Early efforts to provide such a papermaking fabric are disclosed in U.S. Pat. No. 3,301,746 which discloses the use of square, diagonal, twill and semi-twill weaves. Another early effort is disclosed in U.S. Pat. No. 3,974,025 which discloses using the back surfaces of heretofore known papermaking fabrics. Another development in papermaking fabrics is disclosed in U.S. Pat. No. 4,239,065 to Trokham. This patent discloses a papermaker's fabric having a forming surface comprised of successive diagonal rows of co-planar cross-overs forming individual pockets across and along the length of the fabric. U.S. Pat. No. 5,228,482 discloses a paper forming fabric similar to that of Trokham. Here the cross-overs forming the successive rows of pockets are multiplanar. U.S. Pat. Nos. 4,239,065 and 5,228,482 disclose papermaking fabrics having successive diagonal row of individual pockets. These rows of pockets form the paper support surface of the fabric as there are no intervening support surface areas i.e. strips, formed between them.
These earlier patents disclose papermaking fabrics which produce paper having successive rows of pillows or uncompressed areas surrounded by lineaments of compressed areas. The rows of pillows and lineaments are arranged to extend transverse or diagonally of the paper.
Accordingly, an object of the instant invention is to provide a papermaking fabric capable of producing paper of high bulk and increased strength.
Another object of the invention is to provide a papermaking fabric capable of producing paper of increased softness and absorbability.
A further object of the invention is to provide a paper imprinting fabric which produces paper having continuous compressed diagonal strips arranged over its surface.
A further object of the invention is to provide a papermaking fabric having a product support surface which produces uniform fiber orientation.
A further object of the invention is to provide a product support surface which provides increased fiber adhesion. A further objects of the invention is to provide a papermaking fabric having a product support surface comprised of diagonal rows of pockets separated by diagonal strips or planar support surface areas.
A further object of the invention is to provide a papermaking fabric which allows increased heat transfer.
A further object of the invention is to provide a papermaking fabric which produces a paper product having both diagonal and transverse rows of pillows.